Liang Ru-Ping, Gan Gui-Hua, Qiu Jian-Ding
Department of Chemistry and Institute for Advanced Study, Nanchang University, Nanchang, PR China.
J Sep Sci. 2008 Aug;31(15):2860-7. doi: 10.1002/jssc.200800149.
A novel and simple method based on layer-by-layer (LBL) technique has been developed for the modification of the channel in PDMS electrophoresis microchip to create a hydrophilic surface with a stable EOF. The functional surface was obtained by sequentially immobilizing chitosan and deoxyribonucleic acid (DNA) onto the microfluidic channel surface using the LBL assembly technique. Compared to the native PDMS microchips, the contact angle of the chitosan-DNA modified PDMS microchips decreased and the EOF increased. Experimental conditions were optimized in detail. The chitosan-DNA modified PDMS microchips exhibited good reproducibility and long-term stability. Separation of uric acid (UA) and ascorbic acid (AA) performed on the modified PDMS microchip generated 43,450 and 46,790 N/m theoretical plates compared with 4048 and 19,847 N/m with the native PDMS microchip. In addition, this method has been successfully applied to real human urine samples, without SPE, with recoveries of 97-105% for UA and AA.
基于层层（LBL）技术开发了一种新颖且简单的方法，用于修饰聚二甲基硅氧烷（PDMS）电泳微芯片中的通道，以创建具有稳定电渗流（EOF）的亲水性表面。通过使用LBL组装技术将壳聚糖和脱氧核糖核酸（DNA）依次固定在微流控通道表面上，获得了功能表面。与天然PDMS微芯片相比，壳聚糖-DNA修饰的PDMS微芯片的接触角减小，电渗流增加。详细优化了实验条件。壳聚糖-DNA修饰的PDMS微芯片表现出良好的重现性和长期稳定性。在修饰的PDMS微芯片上对尿酸（UA）和抗坏血酸（AA）进行分离，理论塔板数分别为43,450和46,790 N/m，而天然PDMS微芯片的理论塔板数分别为4048和19,847 N/m。此外，该方法已成功应用于实际人体尿液样本，无需固相萃取（SPE），UA和AA的回收率为97-105%。
